The invention relates generally to a method for reducing and/or preventing the buildup of plaque and calculus, commonly called tartar, on the teeth of domestic animals.
Plaque is formed as a result of bacteria living in the mouth. Bacteria live on remnants of food in the mouth. When bacteria combine with saliva and food debris in the channel between the tooth and gum, plaque forms and accumulates on the tooth. When bacteria continue to grow in the plaque and, as calcium salts are deposited, the plaque hardens to become a limestone-like material called calculus or tartar. In many animals, especially cats and dogs, plaque and tartar accumulation is associated with inflammation of the gums (gingivitis) and can progress to severe periodontal disease. Some animals, especially cats, have been found to have a hypersensitivity or allergic reaction and are called ‘plaque-intolerant’. This results in a disease called lymphocytic-plasmacytic gingivitis stomatitis, which affects the entire mouth. In this disease, severe inflammation occurs where the tooth meets the gum line. Chronic gingivitis, periodontitis, and stomatitis can cause severe pain. The animal's behavior may change—irritability, aggressiveness, depression or reclusiveness may be seen. The cat may drool excessively, have difficulty eating or not eat at all. They may have bad breath and may not be grooming themselves adequately. Their gums bleed very easily.
Accordingly, it's essential to remove all plaque and calculus and keep it off. This may be accomplished by daily brushing or the use of plaque controlling products such as chlorhexidine gels and rinses. Unfortunately, even with this intensive care, the disease may progress. Perhaps, the only way to cure the disease and eliminate the very painful lesions may be to extract the teeth. In cases of juvenile onset gingivitis, professional teeth cleaning every 2 months and once—to twice—daily brushing at home for the first year or so of their life, may allow them to revert to a more normal status as they age. Of course, brushing the teeth of an animal is extremely difficult and time consuming.
Other methods for reducing plaque include the daily application of inhibitors that interfere with the calcification of dental plaque by saliva. Such crystal growth inhibitors include soluble pyrophosphates, sodium tripolyphosphate, soluble diphosphonates and certain zinc compounds, such as zinc chloride. U.S. Pat. No. 5,296,217 discloses the use of sequestering agents that are applied as coatings to dry dog food. Such sequestering agents form soluble calcium complexes in saliva and dental plaque fluids to prevent further plaque growth. The preferred sequestering agent disclosed in the '217 patent is sodium hexametaphosphate (HMP) used at levels from 0.5 to about 3.0% by weight of the dry dog food.
U.S. Pat. No. 5,618,518 discloses a variety of chew products, such as a rawhide chew product, which are provided with HMP to reduce the buildup of dental calculus by chewing for an extended period of time. Other rawhide products are disclosed in U.S. Pat. Nos. 5,114,704 and 5,011,679 in which inorganic pyrophosphate compounds are coated on the rawhide product.
U.S. Pat. No. 6,080,419 provides a method to prevent, inhibit, or reduce dental calculus deposits or formation on the teeth of a dental calculus forming animal comprising exposing the teeth to a food product comprising an acidulent amount of phosphoric acid, wherein said food product further comprises an amount of a polycarboxylic acid sequestering agent effective to prevent, inhibit, or reduce dental calculus deposits or formation.
Milk products and milk components have been reported to inhibit bacteria in the mouth that contribute to dental caries in certain animal species such as rodents and humans. For example, U.S. Pat. No. 5,833,953 discloses the reduction of caries through the use of cow's milk which contains fluorine salts.